Sleep sensing device

ABSTRACT

The invention relates to apparatus for sensing drowsiness of an operator of a motor vehicle which includes a multiple contact sensing switch coupled to or actuated by movement of the steering mechanism of the motor vehicle, means for maintaining a predetermined charge on a condenser in a relay time constant circuit under one condition of motor vehicle operation, means for discharging said condenser at a predetermined rate if the mode of steering the vehicle is changed, and alarm means actuated by said relay when said condenser&#39;&#39;s charge level reaches a predetermined level and the output of a generator mechanically coupled to the vehicle drive means and electrically coupled to the alarm circuit exceeds a predetermined voltage. The output of this generator increases with an increase in road speed of the vehicle. An alarm relay placed in series with the time delay relay contacts controls the operation of the alarm signal. The pull in voltage for this relay is selected so that only when the vehicle reaches a certain selected minimum speed will it be possible to have the alarm relay actuate. It will actuate at any speed above the minimum speed if the driver does not actuate the steering wheel within the time delay interval.

United States Patent 1 3,594,772

[72] Inventor Donald D. Setser Primary Examiner-John W Caldwell Tulsa.Okla. Assistant ExaminerJ. Michael Bobbitt [21 A pl. No 52.018AttorneysGrisWOld and Burdick and E. D. Ayers [22] Filed Aug. 12, 1968 a[45] Patented July 20, 1971 l 73] Assignee The Dow chemical comp'nyABSTRACT: The invention relates to apparatus for sensing Midland, Mich.

drowsiness of an operator of a motor vehicle which includes a multiplecontact sensing switch coupled to or actuated by movement of thesteering mechanism of the motor vehicle, means for maintaining apredetermined charge on a condenser in a relay time constant circuitunder one condition of motor vehicle operation, means for dischargingsaid condenser at a [54] SLEEPSENSING DEVICE predetermined rate if themode of steering the vehicle is 4 changed, and alarm means actuated bysaid relay when said 608mm g condensers charge level reaches apredetermined level and [52] U.S. Cl 340/279, the out ut of a generatormechanically coupled to the vehicle 200/6154, drive means andelectrically coupled to the alarm circuit ex- 511 lnt.Cl ..G08b 21/00medsapredetermined voltage,

[50] Field of Search 180/97; Th output f thi n rator increases with anincrease in 2 61.56, /5 52 F, road speed of the vehicle. An alarm relayplaced in series with 56, 279 the time delay relay contacts controls theoperation of the alarm signal. The pull in voltage for this relay isselected so [56] References Cited that only when the vehicle reaches acertain selected UNlTED STATES PATENTS minimum speed will it be possibleto have the alarm relay ac- 3,222,639 12/ 1965 Kayser, Jr 340/279 tuate.It will actuate at any speed above the minimum speed if 2,575,926 11/1951 Murray 340/279 the driver does not actuate the steering wheelwithin the time 3,227,998 1/1966 Platt 340/279 delay interval.

d b0 er 6 09 power- SLEEP SENSING DEVICE BACKGROUND OF THE INVENTIONThis invention relates to apparatus for detecting sleepiness ordrowsiness of the driver of an automotive vehicle and for producing awarning or detection of such sleepiness or drowsiness.

The problem of detecting sleepiness or drowsing in a driver of a motorvehicle has been prevalent since the development of automotivetransportation.

Attempts to solve the problem have included foot switches which must bekept activated by pressure applied by the drivers foot, with an alarmsounding when the drowsy driver inadvertently moves his foot. Anotherdevice utilizes a set of electrical contacts attached to the eyelids ofthe driver. Closing of the driver's eyes completes the electrodecontacts and actuates an alarm.

The prior art attempts to solve the problem of the sleepy or drowsydriver have had one or more shortcomings.

Either the devices have been attached to the driver or the driver mustretain physical contact with the device, and such features are notacceptable as is desired.

Accordingly, a principal object of this invention is to provideimprovedapparatus for sensing sleepiness or drowsiness in a driver of amotor vehicle.

Another object of this invention is to provide an improved apparatus fordetecting sleepiness or drowsiness of a driver of a motor vehicle inwhich the apparatus is not contacted by the driver.

This invention relates to means for detecting sleepiness or drowsinessin a driver of an automotive vehicle. An electrical sensing switch iscoupled to the steering mechanism of the vehicle whereby the normalmoving of a steering wheel results in frequent movement of the contactsof the switch.

Actuation of the multicontact switch either charges a charge transfercondenser or, depending on movement of the vehicles steering wheel,transfers the charge of the transfer condenser to a time constantcircuit comprising a storage condenser across which is coupled a relayand a variable resistance element. The value of the charge transfercondenser determines the charging rate of the relay time delay circuit.

When the steering operation occurs energy is taken from a battery by thecharge transfer condenser and transferred to the relay time constantcircuit. When the electrical potential of the circuit is greater thanthe pull in potential of the relay, the relay will operate. The normallyclosed contacts of this relay are connected in series with an alarmrelay and a voltage generator.

The voltage generator is driven by an adapter which is attached to thespeedometer drive cable outlet from the vehicles transmission, wheel ordifferential. The voltage output of the generator is a function of theroad speed of the vehicle. When the vehicle is stopped, there is nooutput from the generator.

The output of this generator increases with an increase in road speed ofthe vehicle. An alarm relay placed in series with the time delay relaycontacts controls the operation of the alarm signal. The pull in voltagefor this relay is selected so that only when the vehicle reaches acertain selected minimum speed will it be possible to have the alarmrelay actuate. It will actuate at any speed above the minimum speed ifthe driver does not actuate the steering wheel within the time delayinternal.

In accordance with this invention there is provided apparatus forsensing drowsiness of an operator of a motor vehicle which includes amultiple contact sensing switch coupled to or actuated by movement ofthe steering mechanism of the motor vehicle, means for maintaining apredetermined charge on a condenser in a relay time constant circuitunder one condition of motor vehicle operation, means for dischargingsaid condenser at a predetermined rate if the mode of steering thevehicle is changed, the alarm means actuated by said relay when, saidcondensers charge level reaches a predetermined level. i

The invention, as well as additional objects and advantages thereof,will be best understood when the following detailed description is readin connection with the accompanying drawing, in which:

- FIG. 1 is a diagrammatical view of apparatus in accordance with thisinvention;

FIG. 2 is a schematic diagram of one embodiment in accordance with thisinvention;

FIG. 3 is a schematic diagram of a modification of the embodiment ofFig. 2, and

HO. 4 is a schematic diagram of an alternative embodiment of thisinvention.

Referring now to the drawings, and particularly to Fig. 1, there isshown steering apparatus 10 for a motor vehicle (not shown) having asteering sensor switch 12 mechanically coupled thereto. The switch 12 iselectrically coupled by cable 20 to a sleep sensor circuit 14 which iscoupled by cable 22 to an alarm 18, such as a bell or flashing light,for example. The generator 16 is coupled to the vehicles transmission 26or differential by mechanical coupling means 26 and 28 and to the sensorby means 24.

Referring now to the circuits of Fig. 2, which is a manual time delaysensing apparatus, the steering sensor switch, indicated generally bythe numeral 30, has its movable armature contact coupled by means ofwire 40 to one side of a charge transfer capacitor 38. One fixedterminal 32 of the switch 30 is coupled by means of wire 74 to a battery72.

The other terminal of the electrical energy source or battery 72 iscoupled to a common conductor 94 by means of a wire 80. The otherterminal of the charge transfer capacitor 38 is coupled to the conductorby means of a wire 42.

The second fixed terminal 34 of the switch 30 is coupled by means of awire 84 to one terminal of a storage condenser 44 whose other terminalis coupled to the conductor 94 by means of wire 82. A variableresistance element 48 and relay coil 46 are coupled in parallel acrossthe storage condenser 44.

The terminal of the movable armature contact 54 of relay 50, of whichthe coil 46 is a part, is influenced by the degree of energization ofthe coil 46, and is coupled to the conductor 94 through wire 86.

The relay contact 54 is left open, while the fixed contact 52 is coupledto the common conductor 94 through series connected relay coil 58 ofrelay 62, generator 60, and wires 88, 102, and 90.

The movable armature contact 68 of relay 62 is coupled to the conductor74 (connected to one side of the battery 72) by means of wire 76. Thefixed relay contact 64 is floating while the other fixed contact 66 iscoupled to the other side of the battery 72 through series connectedwires 78, 80, 92, and alarm element 70.

In operation, normal movement, even though slight, of the steeringapparatus 10 will cause the steering sensor switch (12 in FIG. 1, 30 inFig. 2) to move its armature element 36 between the fixed contacts 32 or34.

If the movable contact 36 sets against contact 32, energy from thedirect current electrical energy source, battery 72, is fed into thecharge transfer condenser 38. If the movable contact 36 is contactingfixed contact 34, energy from the charge transfer condenser 36 istransferred to the time constant circuit comprising parallel connectedstorage condenser 44, variable resistance element 48 and relay coil 46.

If the electrical potential of the time constant circuit is less thanthe pull in potential of the contacts of relay 62 because ofinsufficient transfer of energy from the condenser 38, the movablearmature contact 54 is connected to the contact 52 which is seriesconnected to the conductor 90 through the relay coil 58 and generator60, thus completing a circuit to place the relay coil 58 in parallelacross the output of the generator 90. If the motor vehicle to which thegenerator is coupled exceeds a predetermined speed, the voltage outputof the generator 60 energizes coil 58 sufficiently to move armaturecontact 68 of relay 62 against fixed contact 66, thus completing thecircuit to place battery 72 across the alarm device 70 and actuate thealarm.

The capacity of condenser 38 controls the amount of possible energytransfer (per each transfer time) to the storage condenser 44, while thevalues of the coil 46 and resistance 48 determine the time of dischargeof the storage condenser 44. Thus, unless movement of the steeringapparatus occurs to a degree sufficient to charge the condenser 38 andthen transfer the charge to the storage condenser before the storagecondenser discharges sufficiently to let the armature 54 contactterminal 52, the alarm 70 will operate if the output of the generator 60exceeds a preset amount.

The circuit of Fig. 3 is basically that of Fig. 2, except that a driveelement 96, such as a solenoid driven arm, is coupled to the generator60 by means of conductors 94 and 100. Mechanical coupling means 98controls the resistance value of the resistance 44 inversely as thespeed of the vehicle, based on the output of the generator 60. (In asimilar fashion, a feedback voltage from the generator may be used todecrease the time taken for the relay to deactivate as steering activitydecreases by blocking a portion of the voltage across the storagecapacitor.) Thus, as the vehicle increases speed, the resistance of theresistor 48 decreases, decreasing the time constant and requiring morefrequent slight movement of the steering apparatus of the vehicle toprevent the actuation of the alarm 70. In the circuit shown in Fig. 4, adirect current energy source, such as the battery 104, is coupled bymeans of wire 148 to the moving armature contact 112 or relay 108 and byseries connected wires 160, 176, 178 to one terminal of an alarm device106. The fixed relay contact 114 is electrically connected to the othertenninal of the alarm device 106 by wire 158. The fixed relay terminal110 is floating. A relay 116 has its movable armature contact 120coupled by series connected wires 150, 154, 156 to coil 124 of relay 108and generator 126 to the common conductor 178. Fixed relay terminal 118is floating while fixed relay contact 122 is coupled to the commonconductor 178 through wire 152.

The actuating coil 128 of relay 116 is coupled across a storagecondenser 130 which is coupledacross the battery 104 on one side bywires 146, 164 and variable resistor 132 and on the other side byconductors 162, 178 and 176.

A sleep sensor switch 134 has its movable armature contact element 138coupled by means of conductor 168 to one side of charge transfercondenser 142. The other terminal of the condenser 142 is coupled toconductor 178 by the wire 170. The fixed contact 136 of switch 134 isconnected through conductors 172, 174 and resistance 144 to conductor178.

The other fixed contact 140 of switch 134 is coupled by means of wire166 to the side of condenser 130 to which the variable resistor 132 iscoupled.

In the apparatus shown in Fig. 4, the time delay circuit charges thetime constant condenser 130 through the variable resistance 132. Whenthe voltage across the condenser 130 is greater than the pull in voltageof the relay 116, the relay 116 will actuate and complete the circuitwhereby relay 108 may be actuated if the voltage output of the generator126 is sufficient.

The principal functional difference between the apparatus of Fig. 4, andthe embodiments of Figs. 2 and 3 is that in this circuit the delay relay116 actuates the alarm circuit on activation of the relay rather than ondeactivation of the time delay relay as occurs in Figs. 2 and 3.

Further, in Fig. 4. the charge transfer condenser 142 removes chargefrom the condenser 130, which opposite to the function of the chargetransfer condenser in Figs. 2 and 3.

In normal driving operation, the charge transfer condenser 142 removespart of the energy from the time constant condenser 130 and dischargesit through the resistor 144. Such more or less continuous chargetransfer action prevents the voltage across the time constant condenser130 from reaching the voltage required to actuate the time delay relay116.

What 1 claim is:

1. Apparatus for sensing sleep or drowsiness of a driver of a motorvehicle or the like, comprising A. An electrical switch coupled tosteering apparatus of a motor vehicle, said switch being a single polemultiple throw type switch, the coupling to said steering apparatusbeing such that a small movement of the steering apparatus moves thesingle pole of said switch to one pole or another,

R. a charge transfer condenser;

C. a time constant circuit including a storage condenser and at least acoil of a first relay, said coil being coupled across said storagecondenser, said first relay having a movable contact and at least onefixed terminal contact;

D. means for electrically energizing said charge transfer condenser whensaid pole is at one throw of said switch;

E. means for transferring electrical energy from said transfer condenserto said storage condenser when said pole is at another throw ofsaidswitch;

F. a second relay having at least a coil, a movable contact and a fixedcontact and having its coil electrically coupled to a generator which ismechanically coupled to the drive means of said vehicle, said coil andsaid generator being connected in series between said movable contactand one fixed contact of said first relay, said movable contact beingheld away from said fixed contact if said electricai energy from saidtransfer condenser is transferred to said storage condenser in excess ofa predetermined rate; and

G. an electrically actuated alarm device and electrical energy sourceconnected in series across said fixed and movable contacts of saidsecond relay whereby when said generator and coil circuit are completedand the generator output exceeds a predetermined minimum output thefixed and movable contacts of said second relay are joined and saidalarm device is actuated.

2. Apparatus in accordance with claim 1, wherein said means forelectrically energizing said charge transfer condenser and saidelectrical energy source are a single direct current source.

3. Apparatus in accordance with claim 1, wherein a variable resistor iscoupled across said storage condenser.

4. Apparatus in accordance with claim 3, whereinresistance valueportioning means are coupled between said generator and said variableresistor.

5. Apparatus for sensing sleep or drowsiness of a driver of a motorvehicle or the like, comprising A. an electrical switch coupled tosteering apparatus of a motor vehicle, said switch being a single-polemultiple throw type switch, the coupling to said steering apparatusbeing such that a small movement of the steering apparatus moves thesingle pole of said switch to one terminal or another B. a chargetransfer condenser;

C. a time constant circuit including a storage condenser and at least acoil of a first relay, said coil being coupled across said storagecondenser, said first relay having a movable contact and at least onefixed terminal contact;

D. means for electrically energizing said storage condenser;

E. means for transferring electrical energy fror" said storage condenserto said charge transfer conde ,er when said pole is at one throw of saidswitch;

G. a second relay having at least a coil, a movable contact and a fixedcontact and having its coil electrically coupled to a generator which ismechanically coupled to the drive means of said vehicle, said coil andsaid generator being connected in series between said movable contactand one fixed contact of said first relay, said movable contact beingheld away from said fixed contact if said electrical energy from saidtransfer condenser is transferred to said storage condenser at less thana predetermined rate; and

H. an electrically actuated alarm device and electrical energy sourceconnected in series across said fixed and movable contacts of saidsecond relay whereby when said generator and coil circuit are completedand the generator output exceeds a predetermined minimum output themeans for electrically energizing said storage condenser and saidelectrical energy source are a single direct current source.

1. Apparatus for sensing sleep or drowsiness of a driver of a motorvehicle or the like, comprising A. An electrical switch coupled tosteering apparatus of a motor vehicle, said switch being a single polemultiple throw type switch, the coupling to said steering apparatusbeing such that a small movement of the steering apparatus moves thesingle pole of said switch to one pole or another, B. a charge transfercondenser; C. a time constant circuit including a storage condenser andat least a coil of a first relay, said coil being coupled across saidstorage condenser, said first relay having a movable contact and atleast one fixed terminal contact; D. means for electrically energizingsaid charge transfer condenser when said pole is at one throw of saidswitch; E. means for transferring electrical energy from said transfercondenser to said storage condenser when said pole is at another throwof said switch; F. a second relay having at least a coil, a movablecontact and a fixed contact and having its coil electrically coupled toa generator which is mechanically coupled to the drive means of saidvehicle, said coil and said generator being connected in series betweensaid movable contact and one fixed contact of said first relay, saidmovable contact being held away from said fixed contact if saidelectrical energy from said transfer condenser is transferred to saidstorage condenser in excess of a predetermined rate; and G. anelectrically actuated alarm device and electrical energy sourceconnected in series across said fixed and movable contacts of saidsecond relay whereby when said generator and coil circuit are completedand the generator output exceeds a predetermined minimum output thefixed and movable contacts of said second relay are joined and saidalarm device is actuated.
 2. Apparatus in accordance with claim 1,wherein said means for electrically energizing said charge transfercondenser and said electrical energy source are a single direct currentsource.
 3. Apparatus in accordance with claim 1, whereiN a variableresistor is coupled across said storage condenser.
 4. Apparatus inaccordance with claim 3, wherein resistance value portioning means arecoupled between said generator and said variable resistor.
 5. Apparatusfor sensing sleep or drowsiness of a driver of a motor vehicle or thelike, comprising A. an electrical switch coupled to steering apparatusof a motor vehicle, said switch being a single pole multiple throw typeswitch, the coupling to said steering apparatus being such that a smallmovement of the steering apparatus moves the single pole of said switchto one terminal or another B. a charge transfer condenser; C. a timeconstant circuit including a storage condenser and at least a coil of afirst relay, said coil being coupled across said storage condenser, saidfirst relay having a movable contact and at least one fixed terminalcontact; D. means for electrically energizing said storage condenser; E.means for transferring electrical energy from said storage condenser tosaid charge transfer condenser when said pole is at one throw of saidswitch; G. a second relay having at least a coil, a movable contact anda fixed contact and having its coil electrically coupled to a generatorwhich is mechanically coupled to the drive means of said vehicle, saidcoil and said generator being connected in series between said movablecontact and one fixed contact of said first relay, said movable contactbeing held away from said fixed contact if said electrical energy fromsaid transfer condenser is transferred to said storage condenser at lessthan a predetermined rate; and H. an electrically actuated alarm deviceand electrical energy source connected in series across said fixed andmovable contacts of said second relay whereby when said generator andcoil circuit are completed and the generator output exceeds apredetermined minimum output the fixed and movable contacts of saidsecond relay are joined and said alarm device is actuated.
 6. Apparatusin accordance with claim 5, wherein said means for electricallyenergizing said storage condenser and said electrical energy source area single direct current source.